Production of dyestuff intermediates



PatenteclDe c. 1, 1931 UNITED STTES PATENT OFFICE VJILLIAM SliHTI-I AND JOHN" THOIvIAS, OF GRANGEMOUTH, SCOTLAND, ASSIGNORS'TO SCOTTISH DYES LIMITED, OF GRANGEMOUTH, SCOTLAND PRODUCTION OF DYESTUFF INTERMEDIATES N0 Drawing. Application filed April 22, 1930, Serial No. 4463299, and in Great Britain April 16, 1929.

" among other things that we can obtain valuable 1: 1-dianthraquinonyl derivatives containing acid substituents in the 2 2-positions, such as chlorine, bromine or sulphonic acid groups by taking anthraquinone derivatives containing chlorine, bromine or sulphonic acid substituents in the 2-position and chlorine or bromine in the 1-position and heating with copper powder.

The anthraquinone derivative containing the halogen atom in the alpha-position, for instance, bromine, may be obtained by starting from 1-amino-2-sulpho-antliraquinone and replacing the amino group, for instance, bromine, and then after replacement, the treatment with a metallic powder can be carried out.

The invention in brief consists in the process which comprises the production of 1:1- dianthraquinonyls containing acid substituents in the 2:2-positions or their derivatives by the condensation of anthraquinone derivatives containing acid substituents in. the 2-position and reactive groups in the 1- position, or their derivatives.

The invention also consists in the process which comprises the production of 1: 1- dianthraquinonyls containing acid substituents in the 2: 2-positions such as chlorine. bromine or sulphonic acid groups, by taking anthraquinone derivatives containing a halogen substituent in the l-position and an acid substituent in the 2-position such as chlorine, bromine or sulphonic acid and treating with copper, special importance being at tached to the production of 1:1-dianthra quinonyl derivatives containing acid substituents in the 2:2-position in which the acid substituents are halogen atoms, particu larly chlorine atoms.

The invention also consists in processes substantially as described, in products when made by those processes or by thelr obvious chemical equivalents.

The accompanying diagram illustrates what may be regarded as the structural formula of the 2: 2' dichlor 1: 1' dianthra quinonyl to which we refer herein.

The following examples illustrate how the invention may be carried into effect, references to parts and to percentages being to parts and percentages by weight Ewample 1 Emample 2 This illustrates the production of 1: 1-dianthraquinonyl derivatives containing acid substituents in the 2 2-position in which the acid substituents are halogen atoms.

2 parts 1.2-dibrom-anthraquinone 1 part copper 4 parts naphthalene.

The above mixture is well stirred at the boil for several hours, and after cooling to about 120, 4parts solvent naphtha are added and the mixture filtered at 100 C. washed with solvent naphtha and dried. The excess copper is removed by boiling with dilute nitric acid filtered, washing acid free, and dried. Theproduct isa pale yellow crystalline powder I 7 General In The invention is not limited to the above I examples. i 1 r The group in the .a pQSlti0I1..may consist,v for instance, of an acid group, for example, a ihalogen, or it may consistof an amino 15 group and'co ndensation may he carried out by treatingthe acid groupwith v a metalsuch as copperiofr, by diazotizing theamino group and treating with copper, either with or with: out intermediate replacement of the-amino groupiw th halog n s Havingow, describedour invention, What 1 We .cl a'im as-n ew anddesire tosecure by Let ters Patent isz 1 1. The rocess'which comprises the profl qduction of 1:;1-dianthraquinonyls containingac-id substituents in-the 2 2-p.osi-tions by the condensation of anthraquinone containing acid substituents selected from the grou consisting; of chlorine, bromine and sulphouic 1*! acid in the 2-position and reactive substituentsselected from the group consisting of chlorine and brong inein label-position, and heating with copperpowder.

2. A process forxtheprocluc-tion of 1: 1-- e thr lq iu nylis containing chlorine in the 2:2"-position;s;, boiling 1:;2-dichloro-an.- thraquinone with copper powder-n,

In .testimony whereof; .we (have signed our; names-,tothis.specification;

' WILLIAMSMITHM J 01m. THOMAS; 

